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the ground; the roots are creeping and aromatic, having the taste and smell of the snake-root (Aristolochia).

We have now finished a review of the class Gynandria; although many species of it are native to this country, you will not so readily procure specimens of this as of most other native plants. The ladies' slipper, milk-weed, and dogsbane, you can often find, but many of the plants of this family, particu. larly the Orchis tribe, opposing all attempts at cultivation, are to be found only in the depths of the forest, or places little fre quented by man; we may, in this respect, compare them to the aboriginal inhabitants of America, who seem to prefer their own native wilds to the refinements and luxuries of a civilized life.

LECTURE XXXVII.

CLASS XIX.-MONŒCIA, AND XX.-DIŒCIA.

IN all the classes hitherto examined, we have found perfect flowers, that is, those which presented the two important organs on which the artificial system is founded. In the first ten classes, we had only to count the stamens to determine the class, and the pistils to ascertain the order.

In the two next classes, we observed whether the stamens grew upon the calyx or the receptacle, and as before, counted the styles to ascertain the order.

In the two next classes, each having two orders, we were guided by the comparative length of the stamens, and certain appearances of the seeds, in one class, and of the seed vessel in the other.

We next found two classes, where connexion of stamens by means of filaments was the essential character, and whose orders depended upon the number of stamens.

In the great class of compound flowers, we regarded chiefly the circumstance of united anthers; the orders being founded upon certain circumstances relative to the little flowers (florets), which compose the whole flower.

The class which was the subject of our last lecture, presented us with the stamens in a new situation; viz. growing out from the pistil, and the orders were reckoned according to the number of these strange looking stamens, each one of which in general is formed of two masses of glutinous pollen.

Our present inquiry is to be directed to two classes, in which

Concluding remarks-Recapitulation-Two classes now to be considered.

the flowers are imperfect, or both stamen and pistil are not found in the same individual flower. The stamens are infertile, and disappear without any fruit; the pistils contain the germ, and when fertilized by the pollen, produce the fruit.

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In the first order is the Bread-fruit tree (ATROCARPUS), which grows to the height of forty feet, having fruit of an enormous size, hanging from its boughs like apples; it is a native of the East Indies, and much valued for food.

This plant belongs to the third class of Jussieu's method.

Triandria.

In the third order we find a very common plant, called cattail (TYPHA), this grows in swampy meadows, and in stagnant waters, often to the height of four or five feet. The long, brown and hard spike which grows at the summit of the stem (giving rise from its peculiar appearance to the name Cattail), is the catkin; it contains in the upper part, the staminate flowers, having neither calyx nor corolla, the 3 stamens arising from a chaffy or hairy receptacle. The pistillate flowers forming the lower part of the spike, produce each a seed supported in a kind of bristle. This plant is sometimes used by the poorer class of people for beds, but is considered by physicians as unhealthful on account of the properties inherent in its substance.

The sedge or CAREX, is a numerous genus, of which nearly 100 species have been discovered in North America. It is a grass-like plant, but separated from the family of grasses, which are mostly of the 3d class, on account of the monœcious

Class Monœcia, orders-Bread-fruit-Order Triandria-Cat-tail-Sedge or Carex.

character of its flowers. The study of this genus alone, might occupy years; a treatise upon it, called Caricography,* has been lately published by an American botanist.†

The Indian corn (ZEA mays), is found in this order. The top or pannicle, consists of staminate flowers only, and of course never produces corn; the pistillate flowers grow in a spike, enclosed in a husk; each pistil produces a seed called corn; the pistils are very long, forming what is called silk.

Tetrandria.

The 4th order contains the Mulberry-tree (MORUS), of the same natural order as the nettle, having leaves rough, and flowers destitute of beauty.

Pentandria.

The 5th order contains the genus AMARANTHUS, in which is a very common weed, seeming to have some analogy to the pig-weed, not only in natural properties, but in being dignified with a name which forms a striking contrast with its mean appearance.

This genus, however, contains some elegant, foreign species; one of which, AMARANTHUS melancholicus, has received the whimsical name of Love-lies-bleeding; probably from the circumstance of its long, spiral, red flower-stalks, bending over, often reclining upon the ground. Another species called Prince's feather, is always erect. The Cock's-comb is a well known plant of this genus.

The Amaranth, whether from its being a good word to fall in with poetical measure, or from some fancied intrinsic beauty, has ever been a favourite with poets. Milton says of the angels, assembled before the Almighty;

"To the ground,

With solemn admiration, down they cast
Their crowns, inwove with Amaranth and gold;
Immortal Amaranth, a flower which once

In Paradise, fast by the tree of life,

Began to bloom, but soon for man's offence,
To Heaven removed.

With flow'rs that never fade, the spirits elect

Bind their resplendent locks, enwreathed with beams."

In Portugal and other warm countries, the Globe Amaranth is said to be used for adorning the churches in the winter.

*From Carex, caricis.

+ Professor Dewey.

Indian corn-Mulberry-Amaranthus-Different species of the Amaranthus.

Polyandria.

This order contains many of the most useful and beautiful of our forest trees, forming a group or family called Amentaceæ ; this was described under the 15th class of Jussieu's method. Fig. 123, represents a branch of the Corylus (Hazel-nut); at a, is the aments or catkins formed wholly of staminate flowers; at b, is a bract or scale of the ament with adhering stamens ; at c, are the pistillate flowers surrounded with scales; at d, is a pistillate flower, having two styles.

The oak, beech, walnut, chesnut, birch, &c. bear their staminate flowers in nodding aments; their pistillate flowers are surrounded with scales for calyxes. These trees are distinguished by woody, exogenous stems, and perennial, branching roots.

This order contains the genus CALLA, of which we have some native species, and which includes the elegant exotic, CALLA ethiopica, or Egyptian Lily. In this genus, the flowers having neither calyx nor corolla, grow upon that kind of receptacle which is called a spadix; the staminate and pistillate flowers are intermixed, the anthers have no filaments, but are sessile or fixed upon the receptacle; the berries are one celled, many seeded, and crowned with a short style. This spadix thus covered with the fructification, stands erect, surrounded by a spreading, ovate spatha; this, in the Egyptian Lily, is of a pure white, presenting a very showy appearance. Without attention to the structure of the plant, you would probably sup pose the spatha to be the corolla; the leaves are sagittate or arrow form.

Fig. 124.

b

α

The CALLA palustris,* a very common American plant, is represented at Fig. 124; at a, is the spatha, which is ovate, cuspidate and spreading; at b, is the spadix covered with the fructification, the staminate and pistillate flowers being intermixed and uncovered; at c, is a pistil magnified, showing the c style to be very short and the stigma obtuse; at d, is a stamen bearing two anthers.

* From paluster, signifying swampy, or growing in marshy places.

Order Polyandria-Amentaces-Genus Calla-Calla ethiopica-Calla palustris.

The Wild-turnip (Arum), is nearly allied to the Calla; they belong to the family Aroides, which are distinguished by peculiar characteristics; such as their mode of inflorescence, fleshy and tuberous roots, and large, sword-shaped or arrowshaped leaves.

The arrow-head (Sagittaria), is unlike most of the Monocious plants in general appearance; it has a three leaved calyx and three white petals, and is not unlike the Spider's-wort in the form of its flowers. Many species of this very delicate looking plant may be found in autumn, in ditches and stagnant

waters.

Monadelphia.

The 15th order, in which the filaments are united in a column, presents us with the Cucumber tribe (Cucurbitacea); these include not only the proper CUCUMIS, which is an exotic, but some native genera of similar plants; we find here the gourd, squash, watermelon, and pumpkin. These plants have mostly a yellow, 5 cleft corolla, calyx 5 parted, 3 filaments united into a tube, a large berry-like fruit, called a Pepo; this, in the melon, is ribbed, and in the cucumber uneven and warty. We find in the same artificial order a very different family of plants, called Coniferous, or cone bearing plants; these have the staminate flowers in aments, each furnished with a scale or perianth supporting the stamens; the pistillate flowers are in strobilums, each furnished with a hard scale. The stems are

woody, the leaves evergreen, and the juice resinous. natural family belong the pine and cypress.

To this

The character of trees may be studied to advantage at four different seasons: in winter, when the forms of the ramification can be seen in the naked boughs, and the leaf and flower buds examined in their inert state; in spring, when in blossom; in summer, when the foliage is in perfection; and in autumn, when, during the first stages of decay, the mellowness and variety of tints afford beautiful subjects for the pencil of the painter, and the investigation of those who love the study of nature under all her forms.

Aroides-Arrow-head-Order Monadelphia-Cucumber tribe-General charaeter-Cone-bearing plants-Best periods for studying trees.

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